M-3, known for most of its length as Gratiot Avenue, is a north–south state trunkline highway in the Detroit metropolitan area of the US state of Michigan. The trunkline starts in Downtown Detroit and runs through the city in a northeasterly direction along one of Detroit's five major avenues. The highway passes several historic landmarks and through a historic district. It also connects residential neighborhoods on the city's east side with suburbs in Macomb County and downtown.
US Highway 16 (US 16), also called Grand River Avenue for much of its length in the state, was one of the principal roads prior to the post-World War II construction of freeways in the state of Michigan. Before the creation of the United States Numbered Highway System in 1926, the highway had been designated as a state highway numbered M-16. The modern route of Grand River Avenue cuts across the Lower Peninsula in a northwest–southeast fashion from near Grand Rapids to Detroit. Before the late 1950s and early 1960s, US 16 followed other roads between Muskegon and Grand Rapids, and then Grand River Avenue through Lansing to Detroit. In the years immediately preceding the creation of the Interstate Highway System, US 16 was shifted from older roads to newer freeways. Later, it was co-designated as an Interstate. When the gap in the freeway was filled in around Lansing, the US 16 designation was decommissioned in the state. The freeway was solely designated Interstate 96 (I-96) east of Grand Rapids and I-196 west of that city.
M-168 was one of the shortest state trunkline highways in the US state of Michigan, extending just under a mile (1.6 km) from a junction with M-22 in downtown Elberta to the former Ann Arbor Railroad ferry docks. It followed the south shore of Lake Betsie. The highway was commissioned in 1931 and served as a connection to the car ferries until 1984. The road was reconstructed by the Michigan Department of Transportation (MDOT) in preparation to transfer it to village control. That transfer happened on April 24, 2012, and now the former highway is a village street.
M-46 is an east–west state trunkline highway in the US state of Michigan between Muskegon and Port Sanilac, terminating near Lake Michigan and Lake Huron on each end. Except for the north–south segment that corresponds with the US Highway 131 (US 131) freeway between Cedar Springs and Howard City, M-46 is practically a due east–west surface highway. The road runs through rural sections of the Lower Peninsula connecting several freeways including US 31, US 131, US 127 and Interstate 75 (I-75).
M-13 is a 73.339-mile (118.028 km) north–south state trunkline highway that runs through the Saginaw Bay region of the US state of Michigan. It runs from Interstate 69 (I-69) south of Lennon to US Highway 23 (US 23) near Standish. The southern section of the trunkline runs along a pair of county lines in a rural area dominated by farm fields. The highway directly connects the downtown areas of both Saginaw and Bay City. North of the latter city, the Lake Huron Circle Tour follows M-13 along the Saginaw Bay.
M-102 is an east–west state trunkline highway in the US state of Michigan that runs along the northern boundary of Detroit following 8 Mile Road. The highway follows the Michigan Baseline, a part of the land survey of the state, and the roadway is also called Base Line Road in places. As a county road or city street, 8 Mile Road extends both east and west of the M-102 designation, which leaves 8 Mile on the eastern end to follow Vernier Road. The western terminus of M-102 is at the junction of 8 Mile Road and M-5 and the opposite end is at Vernier Road and Interstate 94 (I-94). The 8 Mile Road name extends west to Pontiac Trail near South Lyon with a discontinuous segment located west of US Highway 23 (US 23). The eastern end of 8 Mile Road is in Grosse Pointe Woods, near I-94, with a short, discontinuous segment east of Mack Avenue.
M-125 is a 19+1⁄2-mile-long (31.4 km) state trunkline highway in the US state of Michigan. The highway is entirely within Monroe County with the southern terminus on the Ohio state border near Toledo and a northern terminus at US Highway 24 (US 24) in Frenchtown Township, 5 miles (8.0 km) north of Monroe. M-125 runs through rural farmlands and connects a couple of smaller towns with Monroe. It has an unsigned connector highway that links the main highway with Interstate 75 (I-75).
M-59 is an east–west state trunkline highway that crosses the northern part of Metropolitan Detroit in the US state of Michigan. It runs between Howell at Interstate 96 (I-96) and I-94 on the Chesterfield–Harrison township line near the Selfridge Air National Guard Base. While primarily a multi-lane surface highway, it is a full freeway from just east of downtown Pontiac near Opdyke Road to just east of the Mound Road/Merrill Road exit in Utica. The various surface highway segments are named either Highland Road, Huron Street or Hall Road, with the latter known as an area for shopping and dining. The rural sections west of Pontiac pass through Oakland County lake country, passing through two state recreational areas.
M-53 is a north–south state trunkline highway in the US state of Michigan that connects Detroit to The Thumb region. The highway starts in Detroit at a connection with M-3 and ends in Port Austin, Michigan at M-25. In between, the trunkline passes through the northern suburbs of Metro Detroit, connects to freeways like Interstate 69 (I-69) and provides access to rural farmland. In Macomb County, M-53 follows the Christopher Columbus Freeway and POW/MIA Memorial Freeway, while the remainder of the highway is known as Van Dyke Avenue in the metro area or Van Dyke Road elsewhere. The highway has also been named the Earle Memorial Highway for one of the pioneers of the Good Roads Movement and Michigan's highway system.
M-199 is a state trunkline highway near Albion in the US state of Michigan. The western terminus of the 4.030-mile-long (6.486 km) road is in Sheridan Township at exit 119 off Interstate 94 (I-94). The eastern terminus is a junction with Business Loop I-94 downtown Albion. The entire road is within Calhoun County and runs through rural farm fields outside of Albion; in town it is a residential street. The M-199 designation had previously been applied to a highway in the Upper Peninsula in the 1930s. The current highway was previously part of other highways in the first half of the 20th century before it was transferred to local control around 1960. It was later transferred back to state control in 1998 and remains unchanged since.
M-19 is a north–south state trunkline highway in the US state of Michigan. The trunkline begins northeast of Detroit at a junction with Interstate 94 (I-94) near New Haven and runs northward to a junction with M-142 just east of Bad Axe in The Thumb region of the Lower Peninsula. The highway runs through mostly rural and agricultural areas, connecting several small communities.
M-29 is a state trunkline highway in the US state of Michigan that runs in a south–north direction from Chesterfield Township to Marysville. It generally runs along the shore of Lake St. Clair and the St. Clair River.
M-136 is a state trunkline highway in the US state of Michigan that runs from Brockway to Fort Gratiot in the lower part of The Thumb of the Lower Peninsula. The highway serves as a connector between M-19 on the west and M-25 northwest of Port Huron. In between, the highway runs through rural St. Clair County through farm fields and along a creek and river. The trunkline uses roads that were part of the state highway system in 1919. The M-136 designation was assigned in 1931 and extended to its current length in 1961.
M-121 is a state trunkline highway in West Michigan. The highway follows Chicago Drive, a local roadway, from Zeeland to Grandville. Chicago Drive itself runs past the M-121 segment on either side from Holland to Wyoming. The roadway passes through rural farmland on a route that runs parallel to Interstate 196 (I-196). M-121 forms the main street through the center of Hudsonville as it runs southwest–northeast. It forms a major street through the unincorporated community of Jenison before M-121 terminates at I-196 in Grandville.
M-152 is a state trunkline highway in the US state of Michigan in Cass and Van Buren counties. The highway runs through the Sister Lakes area providing access to the lake cabins and adjoining farmlands. The highway has existed mostly unchanged since the designation was commissioned in the 1930s.
M-154 is a state trunkline highway in the U.S. state of Michigan. It is entirely on Harsens Island at the mouth of the St. Clair River. It is one of only three trunklines in Michigan on islands. The other two are M-134 on Drummond Island and M-185 on Mackinac Island. Access to Harsens Island and M-154 is provided by ferry which runs year round. The highway was first designated in 1931, and realigned on the island within the next two years.
M-155 was a signed state trunkline in the US state of Michigan that served as a spur route from Business Loop Interstate 96 in Howell in Livingston County to the Hillcrest Center, the former Howell State Hospital. It was originally designated in the early 1930s and outlasted the hospital which closed in 1982. The roadway was removed from state maps after 1991 but remains under state maintenance as an unsigned trunkline listed as either M-155 or Old M-155.
Interstate 94 (I-94) is a part of the Interstate Highway System that runs from Billings, Montana, to the Lower Peninsula of the US state of Michigan. In Michigan, it is a state trunkline highway that enters the state south of New Buffalo and runs eastward through several metropolitan areas in the southern section of the state. The highway serves Benton Harbor–St. Joseph near Lake Michigan before turning inland toward Kalamazoo and Battle Creek on the west side of the peninsula. Heading farther east, I-94 passes through rural areas in the middle of the southern Lower Peninsula, crossing I-69 in the process. I-94 then runs through Jackson, Ann Arbor, and portions of Metro Detroit, connecting Michigan's largest city to its main airport. Past the east side of Detroit, the Interstate angles northeasterly through farmlands in The Thumb to Port Huron, where the designation terminates on the Blue Water Bridge at the Canada–United States border.
US Highway 25 (US 25) was a part of the United States Numbered Highway System in the state of Michigan that ran from the Ohio state line near Toledo and ended at the tip of The Thumb in Port Austin. The general routing of this state trunkline highway took it northeasterly from the state line through Monroe and Detroit to Port Huron. Along this southern half, it followed undivided highways and ran concurrently along two freeways, Interstate 75 (I-75) and I-94. Near the foot of the Blue Water Bridge in Port Huron, US 25 turned north and northwesterly along the Lake Huron shoreline to Port Austin.
M-3 at Detroit 
M-59 near Mount Clemens 
